Water flow heating device with protection function

ABSTRACT

The present application provides a water flow heating device with a protection function, including: a heating cylinder, a heating wire disposed in the heating cylinder and a water flow temperature sensor, and a protection circuit respectively connected with the heating wire and the water flow temperature sensor; the protection circuit includes a first voltage comparator, an environmental thermal conductivity detection circuit for detecting an environmental thermal conductivity of the water flow temperature sensor and a protection switch for switching on and off the heating wire; the water flow temperature sensor is connected with an input terminal of the first voltage comparator and the environmental thermal conductivity detection circuit, respectively; an output terminal of the first voltage comparator is connected with the protection switch; and the environmental thermal conductivity detection circuit is connected with an enable terminal of the heating wire. The present application can prohibit the heating wire from being turned on when the water flow is not full or slow, and can also cut off the power supply of the heating wire when an internal temperature of the heating cylinder is too high, thus improving the stability and safety of equipment operation.

FIELD OF TECHNOLOGY

The present application relates to the field of water flow heating devices, in particular to, a water flow heating device with a protection function.

BACKGROUND

In order to increase the water temperature in swimming pools, spa pools and Jacuzzi, one or more water flow heating devices are usually equipped.

A water flow heating device refers to a device that makes the temperature of cold water rise into hot water within a certain period of time through various physical principles. It is generally composed of a heating cylinder, a heating wire and a switch circuit.

However, the working environment of the water flow heating device is complex, and it often encounters water shortage, water flow not filling the heating cylinder or slow water flow, etc. Under these circumstances, starting the water flow heating device will often cause damage to the heating wire, and even cause damage to the insulation protection sleeve outside the heating wire, thereby causing potential safety hazards.

SUMMARY

In view of the problem, the present application is presented to provide a water flow heating device having a protective function that overcomes the problem or at least partially solves the problem.

A water flow heating device with a protection function includes: a heating cylinder, a heating wire disposed in the heating cylinder and a water flow temperature sensor, and a protection circuit respectively connected with the heating wire and the water flow temperature sensor;

the protection circuit includes a first voltage comparator, an environmental thermal conductivity detection circuit for detecting an environmental thermal conductivity of the water flow temperature sensor and a protection switch for switching on and off the heating wire; the water flow temperature sensor is connected with an input terminal of the first voltage comparator and the environmental thermal conductivity detection circuit, respectively; an output terminal of the first voltage comparator is connected with the protection switch; and the environmental thermal conductivity detection circuit is connected with an enable terminal of the heating wire.

Preferably, the protection switch includes a first relay and a second relay; contact terminals of the first relay are respectively connected to a live wire and one end of the heating wire; contact terminals of the second relay are respectively connected to a neutral wire and the other end of the heating wire; and the output terminals of the first voltage comparator are respectively connected to a coil terminal of the first relay and a coil terminal of the second relay.

Preferably, the water flow heating device further includes a protection temperature sensor disposed on an outer surface of the heating cylinder; the protection circuit further includes a second voltage comparator; and the protection temperature sensor is connected with an input terminal of the second voltage comparator, and an output terminal of the second voltage comparator is connected with the protection switch.

Preferably, the water flow heating device further includes a thermoswitch disposed on the outer surface of the heating cylinder; the protection switch is connected to an internal power supply through the thermoswitch.

Preferably, an operating temperature of the thermoswitch is 60° C.±2° C.

Preferably, the heating cylinder is a hollow cylinder disposed horizontally.

Preferably, one side of the heating cylinder is provided with a water inlet, and the other side of the heating cylinder opposite to the water inlet is provided with a water outlet.

Preferably, sizes of the water inlet and the water outlet are equal to a cross section of the heating cylinder.

Preferably, the heating wire is disposed at a bottom of the heating cylinder.

Preferably, the heating wire has a double U shape.

The present application has the following advantages:

in the embodiment of the present application, a heating cylinder, a heating wire disposed in the heating cylinder and a water flow temperature sensor, and a protection circuit respectively connected with the heating wire and the water flow temperature sensor are adopted; the protection circuit includes a first voltage comparator, an environmental thermal conductivity detection, circuit for detecting an environmental thermal conductivity of the water flow temperature sensor and a protection switch for switching on and off the heating wire; the water flow temperature sensor is respectively connected with an input terminal of the first voltage comparator and the environmental thermal conductivity detection circuit; an output terminal of the first voltage comparator is connected with the protection switch; and The environmental thermal conductivity detection circuit is connected with the enable terminal of the heating wire, which can prohibit the heating wire from being turned on when the water flow is not full or slow, and can automatically cut oft the power supply of the heating wire when an internal temperature of the heating cylinder is too high, thus improving the stability and safety of equipment operation and avoiding potential safety hazards.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solution of the present application, the following will briefly introduce the drawings that are desired to be used in the description of the present application. Obviously, the drawings in the following description are merely some embodiments of the present application, from which other drawings may be obtained without exerting inventive effort by those ordinarily skilled in the art.

FIG. 1 is a schematic diagram of a circuit structure of a water flow heating device with a protection function provided by an embodiment of the present application;

FIG. 2 is a schematic diagram of a circuit structure of an environmental thermal conductivity detection circuit provided by an embodiment of the present application; and

FIG. 3 is a structural schematic diagram of the water flow heating device with a protective function provided by an embodiment of the present application.

Reference signs in the drawings are as follows:

100. protection circuit; 101. heating cylinder; 102 heating wire; 103. water flow temperature sensor; 104. environmental thermal conductivity detection circuit; 105. first voltage comparator; 106. first relay; 107. second relay; 108. protection temperature sensor; 109. second voltage comparator; 110. thermoswitch; 201. detection control unit 202. voltage amplifier; 203. high current current source; 204. low current current source.

DETAILED DESCRIPTION OF THE EMBODIMENTS

To make the above purposes, features and advantages of the present application clearer sand easy to understand, the present application is further described in detail in combination with the drawings and the detailed description. Obviously, the described embodiments are part of the embodiments of the present application, but not all of them. Based on the embodiments in the present application, other embodiments obtained by those of ordinary skill in the art without exerting creative efforts all fall within the scope of protection of the present application.

Referring to FIG. 1 , a water flow heating device with a protection function provided by an embodiment of the present application is shown, which can concretely include: a heating cylinder 101, a heating wire 102 disposed in the heating cylinder 101 and a water flow temperature sensor 103, and a protection circuit respectively 100 connected with the heating wire 102 and the water flow temperature sensor 103.

The protection circuit 100 includes a first voltage comparator 105, an environmental thermal conductivity detection circuit 104 for detecting an environmental thermal conductivity of the water flow temperature sensor 103 and a protection switch for switching on and off the heating wire 102. The water flow temperature sensor 103 is connected with an input, terminal of the first voltage comparator 105 and the environmental thermal conductivity detection circuit 104, respectively. An output terminal of the first voltage comparator 105 is connected with the protection switch. The environmental thermal conductivity detection circuit 104 is connected with an enable terminal of the heating wire 102.

In the embodiment of the present application, a heating cylinder 101, a heating wire 102 disposed in the heating cylinder 101 and a water flow temperature sensor 103, and a protection circuit 100 connected with the heating wire 102 and the water flow temperature sensor 103, respectively are adopted. The protection circuit 100 includes a first voltage comparator 105, an environmental thermal conductivity detection circuit 104 for detecting an environmental thermal conductivity of the water flow temperature sensor 103 and a protection switch for switching on and off the heating wire 102. The water flow temperature sensor 103 is connected with an input terminal of the first voltage comparator 105 and the environmental thermal conductivity detection circuit 104, respectively. An output terminal of the first voltage comparator 105 is connected with the protection switch. The environmental thermal conductivity detection circuit 104 is connected with the enable terminal of the heating wire 102, which can prohibit the heating wire 102 from turning on when the water flow is not full or slow, and can automatically cut off the power supply of the heating wire 102 when an internal temperature of the heating cylinder is too high, thus improving the stability and safety of equipment operation and avoiding potential safety hazards.

Hereinafter, a water flow heating device with a protection function in the present exemplary embodiment will be further described.

As an example, the heating cylinder 101 is a pipe through which water flow is provided. The heating wire 102 is disposed inside the heating cylinder 101 near a bottom of the heating cylinder 101, and can heat the water flow inside the heating cylinder 101 when electrified. The water flow temperature sensor 103 is disposed above the heating wire 102 at a position close to the heating wire 102 and at an equal distance from both ends of the heating wire 102, and can detect an internal temperature of the heating cylinder 101 in real time.

The water flow temperature sensor 103 is connected to the input terminal of the first voltage comparator 105 and the environmental thermal conductivity detection circuit 104. On the one hand, the water flow temperature sensor 103 can transmit the internal temperature to the environmental thermal conductivity detection circuit 104 in a form of a voltage signal before the heating wire 101 is turned on, and cooperate with the environmental thermal conductivity detection circuit 104 to play a protective role. It should be noted that, the environmental thermal conductivity detection circuit 104 may operate for a period of time before the heating wire 102 is turned on, specifically, the water flow temperature sensor 103 is heated for a period of time and then stopped heating, in this process, the water flow temperature sensor 103 transmits the internal temperature to the environmental thermal conductivity detection circuit 104 in the form of the voltage signal, the environmental thermal conductivity detection circuit 104 determines whether the heating cylinder 101 is in a state of full water and a water velocity meets the standard according, to rising and falling, speeds of the internal temperature, when the heating cylinder 101 is in a non-full water state or the water velocity does not meet the standard (lower than the standard water velocity), the environmental thermal conductivity detection circuit 104 outputs a disable signal to the enable terminal of the heating wire 102 to inhibit the heating wire 102 from being turned on, thereby protecting the heating wire.

As shown in FIG. 2 , the environmental thermal conductivity detection circuit 104 includes a detection control unit 201, a voltage amplifier 202, a high current current source 203 and a low current current source 204. The detection control unit 201 outputs a first control signal CSCH to the high current current source 203, and the high current current source 203 outputs a higher current CSH to the water flow temperature sensor 103. The detection control unit 201 outputs a second control signal CSCL to the low current current source 204, and the low current current source 204 outputs a lower current CSL to the water flow temperature sensor 103. The water flow temperature sensor 103 outputs a voltage to the voltage amplifier 202. The voltage amplifier 202 outputs an amplified voltage UI to the detection control unit 201. The detection control unit 201 outputs a heating enable signal ENB.

First, the detection control unit 201 controls the high current current source 203 to output CSH to the water flow temperature sensor 103, and controls the water flow temperature sensor 103 to obtain a constant power within a specific period of time, at this time, the temperature of the water flow temperature sensor 103 rises, the voltage amplifier 202 amplifies the voltage on the water flow temperature sensor 103 and sends it to the detection control unit 201. The detection control unit 201 collects the UI and calculates a first temperature change rate dT1/dt of the water flow temperature sensor 103 within a specific time.

The detection control unit 201 then controls the high current current source 203 to turn off the CSH output to the water flow temperature sensor 103, the detection control unit 201 controls the low current current source 204 to output CSL to the water flow temperature, sensor 103, at this time, the power obtained by the water flow temperature sensor 103 is small, and the temperature will drop. The voltage amplifier 202 amplifies the voltage on the water flow temperature sensor 103 and sends it to the detection control unit 201. The detection control unit 201 collects the UI and calculates the second temperature change rate dT2/dt of the water flow temperature sensor 103 within a specific time.

Assuming that when the heating cylinder 101 is in a state of full water and the water velocity is a standard water velocity, the measured dT1/dt and dT2/dt are the first preset change rate and the second preset change rate, then when the heating cylinder 101 is in a state of non-full water state or the water velocity is lower than the standard water velocity, the thermal conductivity of the environment in which the water flow temperature sensor 103 is located is low, dT1/dt is greater than the first preset, change rate, and dT2/dt, is greater than the second preset change rate, and the detection control unit 201 sets the ENB to disable to inhibit the heating wire 102 from being turned on.

On the other hand, the water flow temperature sensor 103 can also transmit the internal temperature to the first voltage comparator 105 in a form of a voltage signal after the heating wire 102 is turned on, and cooperate with the first voltage comparator 105 to play a protective role. It should be noted that when the internal temperature is too high after the heating wire 102 is turned on, the voltage output by the water flow temperature sensor 103 exceeds the voltage reference of the first voltage comparator 105, the first voltage comparator 105 outputs a low level to turn off the protection switch for protection.

In a specific implementation, a non-inverting input terminal of the first voltage comparator 105 is electrically connected to a 5V direct current, and an inverting input terminal of the first voltage comparator is connected to the water flow temperature sensor 103. When the water flow in the heating cylinder 101 is slow or blocked, the water flow in the heating cylinder 101 is overheated, resulting in an increase in the internal temperature of the heating cylinder 101, and when the internal temperature of the heating cylinder 101 exceeds 60° C., the water flow temperature sensor 103 outputs a voltage of 5.02 V to the inverting input terminal of the first voltage comparator 105. At this time, a voltage at the inverting input terminal of the first voltage comparator 105 is greater than a voltage at the non-inverting input terminal, and the first voltage comparator 105 outputs a low level, so that the protection switch is turned off and the heated wire 102 stops working.

In this embodiment, the protection switch includes a first relay 106 and a second relay 107. Contact terminals of the first relay 106 are respectively connected to a live wire L and one end of the heating wire 102. Contact terminals of the second relay 107 are respectively connected to a neutral wire N and the other end of the heating wire 102. The output terminals of the first voltage comparator 105 are respectively connected to a coil terminal of the first relay 106 and a coil terminal of the second relay 107.

It should be noted that both the first relay 106 and the second relay 107 are normally open relays, i.e., the contacts are in an off state when the coils are not energized. By providing the first relay 106 and the second relay 107, the power supply at both ends of the heating wire 102 can be cut off at the same time when the internal temperature of the heating cylinder 101 is too high, thus avoiding potential safety hazards caused by breakage of the insulation protection sleeve outside the heating wire 102.

In a specific implementation, a non-inverting input terminal of the first voltage comparator 105 is electrically connected to a 5V direct current, and an inverting input terminal of the first voltage comparator is connected to the water flow temperature sensor 103. When the internal temperature of the heating cylinder 101 exceeds 60° C., the water flow temperature sensor 103 outputs a voltage of 5.02 V to the inverting input terminal of the first voltage comparator 105, at this time, the voltage at the inverting input, terminal of the first voltage comparator 105 is greater than the voltage at the non-inverting input terminal, the first voltage comparator 105 outputs a low level so that the coil voltages of the first relay 106 and the second relay 107 are lower than the operating voltage, the contacts of the first relay 106 and the second relay 107 are all disconnected, and the heating wire 102 stops working.

In this embodiment, the water flow heating device further includes a protection temperature sensor 108 disposed on an outer surface of the heating cylinder 101. The protection circuit 100 further includes a second voltage comparator 109. The protection temperature sensor 108 is connected with an input terminal of the second voltage comparator 109, and an output terminal of the second voltage comparator 109 is connected with the protection switch. Specifically, the output terminal of the second voltage comparator 109 is connected to a coil terminal of the first relay 106 and a coil terminal of the second relay 107, respectively.

It should be noted that the protection temperature sensor 108 can detect a surface temperature of the heating cylinder 101 in real time, and transmits the surface temperature to the second voltage comparator 109 in the form of a voltage signal. When the surface temperature is too high, the voltage output by the protection temperature sensor 108 exceeds the voltage reference of the second voltage comparator 109, and the second voltage comparator 109 outputs a low level to turn off the protection switch for protection.

In a specific implementation, a non-inverting input terminal of the second voltage comparator 109 is electrically connected to 5V direct current, and an inverting input terminal of the second voltage comparator is connected to the protection temperature sensor 108. When the internal temperature of the heating cylinder 101 exceeds 60° C., the protection temperature sensor 108 outputs a voltage of 5.02 V to the inverting input terminal of the second voltage comparator 109, at this time, the voltage at the inverting input terminal of the second voltage comparator 109 is greater than the voltage at the non-inverting input terminal, the second voltage comparator 109 outputs a low level so that the coil voltages of the first relay 106 and the second relay 107 are lower than the operating voltage, the contacts of the first relay 106 and the second relay 107 are all disconnected, and the heating, wire 102 stops working.

In this embodiment, the water flow heating device further includes a thermoswitch 110 disposed on the outer surface of the heating cylinder 101. The protection switch is connected to the internal power supply BAT through the thermoswitch 110. Specifically, the coil terminals of the first relay 106 and the second relay 107 are respectively connected to the internal power supply BAT through the thermoswitch 110.

It should be noted that the thermoswitch 110 is a normally closed thermoswitch 110, and its temperature sensing component is composed of a bimetallic strip. When the surface temperature of the heating cylinder 101 is lower than the operating temperature, the bimetallic strip is in a free state, the contacts are in a closed state, and the heating wire 102 works normally. When the surface temperature of the heating cylinder 101 exceeds the operating temperature, the bimetallic strip is heated to generate internal stress and acts quickly, and the contacts are opened to cut off the circuit so that the heating wire 102 stops working.

In this embodiment, the operating temperature of the thermoswitch 110 is 60° C.±2° C. In a specific implementation, the thermoswitch 110 is connected to the output terminal of the internal power supply BAT. When the surface temperature of the heating cylinder 101 exceeds 60° C., the thermoswitch 110 is automatically disconnected, so that energization of coils of the first relay 106 and the second relay 107 is stopped, the contacts of the first relay 106 and the second relay 107 are disconnected, and the heating wire 102 stops working.

As shown in FIG. 3 , the heating cylinder 101 is a hollow cylinder disposed horizontally. One side of the heating cylinder 101 is provided with a water inlet and the other side of the heating cylinder opposite to the water inlet is provided with a water outlet. Sizes of the water inlet and the water outlet are equal to a cross section of the heating cylinder 101. It is possible to make the water flow quickly pass through the heating cylinder 101 and avoid water accumulation inside the heating cylinder 101 by disposing the heating cylinder 101 horizontally, setting the water inlet and the water outlet opposite each other, and setting the water inlet and the water outlet to a cross-sectional size.

In this embodiment, the heating wire 102 is disposed at a bottom of the heating cylinder 101. The heating wire 102 has a double U shape. A possibility that the heating wire 102 is exposed to the water surface can be reduced by disposing the heating wire 102 at the bottom of the heating cylinder 101. A contact area between the heating wire 102 and the water flow can be increased by providing the heating wire 102 in a double U shape, thereby speeding up the heat exchange efficiency.

Although preferred embodiments of the embodiments of the present application have been described, additional changes and, modifications may be made to these embodiments once the basic inventive concepts are known to those skilled in the art. Therefore the appended claims are intended to be interpreted to encompass the preferred embodiments as well as all changes and modifications falling within the scope of the embodiments of the present application.

Finally, it should be noted that relational terms such as first and second are used herein only to distinguish one entity or operation from another and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms “comprise”, “include” or any other variation thereof are intended to encompass non-exclusive inclusion, so that a process, method, article or terminal equipment that includes a set of elements includes not only those elements but also other elements that are not explicitly listed, or also elements inherent to such a process, method, article or terminal equipment. In the absence of further limitations, the elements defined by the sentences “comprising a” do not exclude the existence of other identical elements in the process, method, article or terminal equipment including the elements.

The water flow heating device with a protection function provided by the present application is described in detail above, and particular examples are used herein to explain the principle and embodiments of the present invention, and the above description of the embodiments is only used to help understand the methods and core concept of the present application; meanwhile, those of ordinary in the art may make various variations on embodiments and scope of application based on the concepts of the present invention. In view of the foregoing, the contents of the description should not be construed as limitations to the present application. 

1. A water flow heating device with a protection function comprising: a heating cylinder, a heating wire disposed in the heating cylinder and a water flow temperature sensor, and a protection circuit respectively connected with the heating wire and the water flow temperature sensor; the protection circuit includes a first voltage comparator, an environmental thermal conductivity detection circuit for detecting an environmental thermal conductivity of the water flow temperature sensor and a protection switch for switching on and off the heating wire; the water flow temperature sensor is connected with an input terminal of the first voltage comparator and the environmental thermal conductivity detection circuit, respectively; an output terminal of the first voltage comparator is connected with the protection switch; and the environmental thermal conductivity detection circuit is connected with an enable terminal of the heating wire.
 2. The water flow heating device according to claim 1, wherein the protection switch comprises a first relay and a second relay; contact terminals of the first relay are respectively connected to a live wire and one end of the heating wire; contact terminals of the second relay are respectively connected to a neutral wire and the other end of the heating wire; and the output terminals of the first voltage comparator are respectively connected to a coil terminal of the first relay and a coil terminal of the second relay.
 3. The water flow heating device according to claim 1, further comprising a protection temperature sensor disposed on an outer surface of the heating cylinder; the protection circuit further includes a second voltage comparator; and the protection temperature sensor is connected with an input terminal of the second voltage comparator, and an output terminal of the second voltage comparator is connected with the protection switch.
 4. The water flow heating device according to claim 1, further comprising a thermoswitch disposed on the outer surface of the heating cylinder, wherein the protection switch is connected to an internal power supply through the thermoswitch.
 5. The water flow heating device according to claim 4, wherein an operating temperature of the thermoswitch is 60° C.±2° C.
 6. The water flow heating device according to claim 1, wherein the heating cylinder is a hollow cylinder disposed horizontally.
 7. The water flow heating device according to claim 6, wherein one side of the heating cylinder is provided with a water inlet, and the other side of the heating cylinder opposite to the water inlet is provided with a water outlet.
 8. The water flow heating device according to claim 7, wherein sizes of the water inlet and the water outlet are equal to a cross section of the heating cylinder.
 9. The water flow heating device according to claim 1, wherein the heating wire is disposed at a bottom of the heating cylinder.
 10. The water flow heating device according to claim 1, wherein the heating wire has a double U shape. 